Health & Medicine

Fasting Diet Make People More Susceptible to Infection

Benita Matilda
First Posted: Jul 21, 2014 09:41 AM EDT

A new study defies the theories surrounding the benefits of 'Intermittent Fasting' or ' 5:2 diet', stating this popular diet adversely affects the immune system.

For decades, people have been opting for various ways to boost lifespan like intake of vitamin pills and fad diets. In the new study, researchers at the University of Bath's Biology & Biochemistry Department have found evidence that the anti-aging treatments such as intake of anti-oxidants or restricting diet offers temporary benefits they also have some detrimental effects on health.

They found that the '5:2' diet - which celebrities endorse as an effective way of lowering blood pressure, increasing lifespan, protecting against dementia and helping in weight loss - in the long term weakens the immune system making people less able to ward off infections.

In this study, the researchers evaluated four stress and immunity genes in fruit genes in the fruit flies that is known to boost longevity. They studied these genes in order to understand the link between longevity and ability to battle infections. These similar genes are activated by certain 'anti-aging' treatments such as starvation diets or taking antioxidants. These genes in the fruit flies are similar to those present in humans, hence these findings could be implied on humans.

The researchers found that exposure to fungal pathogen extended the lives of the fruit flies by activating the stress and immunity genes. Sadly, in the long term these treatments led to a significant reduction in immune system making the person vulnerable to infection though they extended life and increased fertility.

Dr Nick Priest, Lecturer in Biology & Biochemistry at the University, explained: "Many studies have documented benefits of diet restriction and anti-oxidants consumption, but there is a lack of data on levels of illness in people administered these anti-ageing treatments. We know that certain stresses such as starvation or exposure to pathogens can extend life and increase fertility, but we have found that ironically this has a trade-off in terms of immune function."

The findings supports previous theories like starved mice are more likely to succumb to serious infections. But, there has been a lot more interest in short term benefits than in potential long-term costs.

"There are clear health benefits to diets such as the 5:2 regime, but we need to bear in mind there are side effects. It shows that even the fountain of youth should come with a warning label," Professor Valter Longo said.

The study was documented in the journal Evolution. 

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